1. Field of the Invention
The present invention relates to a machine learning device, a robot system, and a machine learning method for learning an operation for picking up workpieces placed in a random fashion, including a bulk-loaded state.
2. Description of the Related Art
One conventionally-known robot system grips and transports workpieces packed in bulk in a basket-shaped box, using the hand unit of a robot, as disclosed in, e.g., Japanese Patent Nos. 5642738 and 5670397. Such a robot system, for example, obtains the position information of a plurality of workpieces using a three-dimensional measuring device located above a basket-shaped box and picks up the workpieces one by one, based on the obtained position information, using the hand unit of a robot.
Unfortunately, the above-mentioned conventional robot system may preferably involve, e.g., presetting how to extract a workpiece to be picked up, from distance images of a plurality of workpieces measured by a three-dimensional measuring device, and the position at which a workpiece to be picked up is located. It may further be preferable to program, in advance, how to operate the hand unit of a robot when a workpiece is picked up. As a specific example, a human may preferably teach the robot to perform a picking operation of a workpiece, using a teaching pendant.
When the setting for extracting a workpiece to be picked up from distance images of a plurality of workpieces is inappropriate, or an operation program for a robot is not appropriately created, the success rate of picking up and transporting a workpiece by the robot lowers. To improve the success rate, the workpiece detection setting and the operation program for a robot may be preferably refined while searching for an optimal operation of the robot through trial and error by a human.
In consideration of the above-described situation, it is an object of the present invention to provide a machine learning device, a robot system, and a machine learning method which can learn an optimal operation of a robot in picking up workpieces placed in a random fashion, including a bulk-loaded state, without human intervention.